Photospheric magnetogram B_z (left) and surface velocity u_z (right) for t = 10 840 s, before the flux rope and arcade are ordered, shown at the top. Photospheric magnetogram B_z (left) and surface velocity u_z (right) for t = 11 440 s, after the main reconnection event, shown at the bottom. Cyan circles on the magnetograms represent the main positive photospheric root for the arcade, and red circles represent the main positive photospheric roots for the flux rope. The difference in time between the top and bottom panels is 600 s, accounting for roughly one photospheric turnover time.